Out of curiosity, if you're doing something this dramatic, does it make matters easier to remove the front grille and crossmember so that you have more room to work with? That way you could just slide the motor in and out, guess it depends on how big a pain removing the front is. It might also give you better visibility to ensure that everything is buttoned up right.

Gotta say though 275k on a stock motor is pretty cool, gotta love these M50's.